Hydrofoil system for outboard boat



Jan. 5, 1965 R. LOPEZ HYDROFOIL SYSTEM FOR OUTBOARD BOAT 3 Sheets-Sheet 1 Filed Sept. 19, 1962 BY W R W AT TOR NE Y5 Jan. 5, 1965 R. LOPEZ 3,164,118

HYDROFOIL SYSTEM FOR OUTBOARD BOAT Filed Sept. 19. 1962 3 Sheets-Sheet 2 IN VENTOR.

AT TOR NEYS Jan. 5, 1965 R. LOPEZ 3,164,118

HYDROFOIL. SYSTEM FOR OUTBOARD BOAT Filed Sept. 19. 1962 3 Sheets-Sheet 3 RELIEF VALVE H8 RESERVOIR J) INVEN TOR.

M W) I94 BY W W ATTORNEYS hydrofoil;

shown in phantom only,

United States Patent This invention relates to hydrofoils and more especially to means for connecting hydrofoils with a boat hull for convenient movement of the hydrofoils between working positions and retracted positions in which at least a portion, and preferably all, of the hydrofoils are located within the projections of the boat hull in a fore-and-aft direction. The invention also relates to means for combining a hydrofoil equipped boat with a motor support for an outboard motor and with a correlation between the motor support and the hydrofoils for operating both the hydrofoils and the motor supports from common operating mechanism and for changing the depth of immersion of the outboard motor in accordance with the operation of the hydrofoil.

It is an object of this invention to provide improved means for connecting hydrofoils with a boat hull and to provide an improved correlation between the hydrofoils and the support for an outboard motor by which the boat is propelled.

One of the problems encountered with hydrofoil boats, having outboard motors, is that the motor is very deeply immersed in the water when the boat is not foilborne. This results in a high back pressure on the motor exhaust when the boat is traveling at slow speed and this back pressure greatly reduces the power of the motor and impairs the ability of the boat to gain the speed necessary -to make the hydrofoil operative.

It is a feature of this invention that the motor can be moved vertically to change its position with respect to the hull so as to obtain the optimum immersion of the motor propeller when the boat is operating either as a displacement hull or is foilborne at higher speed.

Another object of the invention is to provide mechanism for raising and lowering an outboard motor with respect to a boat transom to which the outboard motor -is connected and for raising and lowering hydrofoils with reference characters indicate corresponding parts in all the views;

FIGURE 1 is a fragmentary rear elevation of a portion of the transom of a boat hull with a hydrofoil connected with the hull and shown in retracted position and with a portion of a motor mount shown connected with the FIGURE 2 is a fragmentary side elevation of the structure shown in FIGURE 1 with the boat transom and the fastenings forconnecting the structure to the transom omitted;

FIGURE 3 is a side elevation of a motor mount shown connected with the transom at a center location, the transom being shown in section;

FIGURE 4 is a view looking down on the mount of FIGURE 3 from above;

FIGURE 5 is a diagrammatic view showing control ice mechanism for operating a motor which moves the mount of FIGURES 3 and 4 to change the vertical position of a motor carried by the mount;

FIGURE 6 is a diagrammatic view showing the way in which the vertical position of an outboard .motor is changed in accordance with the operation of the mount shown in FIGURES 3 and 4; and

FIGURE 7 is a detail view of a control valve used in the mechanism illustrated in FIGURE 5.

FIGURE 1 is a rear view of a boat hull 10 having a transom 11 which is cut down along the upper edge 12 in accordance with conventional practice on outboard motor boats.

A hydrofoil 14 is pivotally connected to a shaft 16 extending through a bearing 18 of a connecting fitting 29. This connecting fitting 20 is secured to the transom 11 by bolts 22 which extend through the transom.

A bracket 26 is fixed to the connecting fitting 20 and extends downwardly into position for connection with the hydrofoil 14 to hold the hydrofoil in a lowered operating position. FIGURE 1 shows the hydrofoil 14 in dotted lines in a raised and partly-retracted position, and shows the hydrofoil in full lines in its fully-retracted position.

The hydrofoil 14 has an end portion 30 which connects with the bracket 26 when the hydrofoil is lowered into working position; and the hydrofoil also has a strut portion 32 and a lower dihedral portion 34.

The hydrofoil 14 is rotatable about a substantially horizontal, fore-and-aft axis about a bearing 38 on the shaft 16. Swinging of the hydrofoil about this bearing 33 shifts the hydrofoil between operative and retracted positions. The shaft 16 is angularly movable about a horizontal axis extending athwartship for purposes of changing the angle of attack of the hydrofoil. This motion of the shaft 16 to change the angle of attack is actuated by control means extending through the connecting fitting 20, but a description of it is not necessary for a complete understanding of this invention.

There is a bracket 42 rigidly connected to the end portion 36 of the hydrofoil; and a link 44 is pivotally connected with the bracket 42 at one end of the link.

he other end of the link 44 has a pivot connection 46 with a flexible cable 48. There is preferably a turnbuckle 50 in this connection of the pivot 46 with the cable 48. i

The flexible cable 48 passes around guide means for changing its direction of travel, and in the construction illustrated the guide means is a pulley 52. Beyond the pulley 52 the flexible cable 48 connects with a motor mount 54.

When the hydrofoil 14 is in its lowered position, the end portion 30 of the hydro-foil is parallel to the bracket 26 and extends in a substantially vertical direction. The link 44 is long enough so that the pivot connection 46 is located above the upper end of the hydrofoil 14 and at a substantial distance above the axis of the bearing 38. Thus pull of the flexible cable 43 against the vertically extending link 44 presses the link 44 against the upper end of the hydro-foil as a fulcrum and rocks the link 44 counter clockwise with resulting similar angular movement of the hydrofoil 14. As the bracket 42 rises, in response to this clockwise rotation of the hydrofoil 14, the link 44 swings clear of its fulcrum contact with the upper portion 3th of the hydrofoil and exerts a straight tension pull on the bracket 42 and the hydrofoil 14. The link 44 is shown in position in which it is exerting such a tension pull in FIGURE 1.

When the hydrofoil 14 reaches the position shown in dotted lines in FIGURE 1, the center of gravity of the hydrofoil 14, indicated by the reference character 56, has moved inboard beyond the axis of the bearing 38 so that further retracting movement of the hydrofoil 14 is obtained by gravity. The center of gravity of the hydrofoil moving from the point to the point 58 as the hydrofoil moves from the dotted line to the full line position shown in FIGURE 1.

7 When the hydrofoil 14 is in fully-retracted position,

it rests on a crank pin or rest 6t? having a limit stop 62 at its outer end. This crank pin 69 is an outward extensionof a crank 64 and the inner end of the crank 64 connects with a shaft as which is preferably of onepiece construction with the crank 64. This shaft as extends through a bearing e8 in a bracket '73 connected to the transorn ll by bolts 72.

At the inboard end of the shaft 66, there is another crank 76, preferably of one-piece construction with a bell crank 77, secured to the shafted; and there is a'spring 78 connected between the end of the crank '76 and a spring anchor 8%) (FIGURE 2) which is attached to the transom 11 by a bolt 32.

This spring '78 urges the crank 76 and the crank 64 to move counter-clockwise from the full-line position shown in FIGURE 1 to the dotted-line position. The total angular movement of the crank d4 is limited to the angle between the full-line and dotted-line position shown in FIGURE 1 by the bell crank '77 secured to the shaft as and movable as a'unit with the cranks es and '76. This bell crank 7'7 has a roller $8 at its lower end which comes in contact with the top edge of the transom 11. when the crank 64 reaches its full-line position; and the bell crank '77. has another roller 9% which comes into contact with the top edge of the transom 11 when the crank 64 reaches its dotted-line position. These rollers 88 and 9% are, therefore, stops for limiting the angular movement ofthe'crank 64.

When not displaced by the hydrofoil 14, the crank 'pin 6% occupies the dotted-line position shown in FIG- URE 1. As the hydrofoil 14 moves toward retracted position, its contact with the pinfib and its further movement to fully-retracted position is a resiliently-retarded movement against the force of the spring 78. The weight of the hydrofoil 14 is suiiicient to hold the spring 58 stretched and the hydrofoil 1.4 is the full-line-lpositionby force of gravity. V

FIGURES 3 and 4 show-the motor mount 54. It ineludes bracket fittings 92 and @3 connected with tr e transom 11 by bolts 96. The motor mount has a motor support @8 with bearing bl cks 99 connected to the front face by bolts Hill. The motor support 93in connected to the transom fittings 92 and 93 by links 1 .92 and 1M. These links 162 and 104, the motor support 93, and the portion of the transom 11 between the fittings 92 and-93 form a folding parallelogram linkage. Thus as the links Th2 and 1694 swing about their pivot connections to the fittings hi.

and 93, the motor support as moves them up and down along an arcuate path but always parallel to itself. .An outboard motor connected to themotor support therefore remains in the same angular position with respect to thetransom as it moves up and down with the motor support.

A center bracket 110 is connected to the transom l1 by bolts 112; and there is a cylinder-and-piston motor 116 connected at its upper end with the center bracket lit? and its lower end with the link 1492. in the construction illustrated, the cylinder-and-piston motor 116 has-a cylinderv 12% with a lug 121 at its head end connected to the link Hi2 by a pivot connection 124; and the motor has a piston rod 126 with a fitting 1Z3 atits upper end connected to the center bracket till by a, pin 39. The cyl-inder-and-piston motor 116 may be a double-acting motor or it may be a single-acting, with working fluid supplied only to the upper sideof its piston for lifting the weight ofan outboard motor on. the motor support 5 8; that is, for moving the links M32 and 1M counter-clockwise; the weight of the outboard motor being relied upon to move the motor mount in the opposite direction.

The limit of travel of the links 162 and 104, and the resulting vertical movement of the motor support 98, are determined by adjustable stops, 1% and 133. These stops are bolted to the transom ii and have threaded portions which can be turned one way or another to move abutments 14 d toward and from the transom 11. There is an abutment surface 142 on the upper part of the link M2 in position to engage the upper stop 7136 and there is an abutment surface M4 on the lower link ies in position to engage the stop i.

The length of the flexible cable 48 is such that it is taut when the motor mount 54 is in raised position and the hydrofoils are in their lowered working position. Thus when the boat is at rest and the hydrofoils are to be moved from working position to retracted position, downward movement of the motor mount 54 pulls the flexible cable 43 so as to lift the hydrofoils into partially retracted position. The flexible cable 48 is connected to the link 1922 sulliciently far from its pivot connection to the fitting 93 so that the displacement of the flexible cable by downward movement of the motor mount 54 is sufiicient to raise the hydrofoil to the dotted line position shown in FIGURE 1 so that further movement into fully retracted position can be by gravity. The outboard motor on the motor mount acts as a counterweight, therefore, when raising the hydrofoils from working to retracted position.

Conversely, movement of the hydrofoils into their lower operative position will raise the motor mount 54. The motor 116 operates, therefore, to move both the hydrofoils and the motor mounts in opposite directions.

After the hydrofoils have been lowered into working position and before the boat gets underway, the flexible cable 48 is disconnected from the motor mount 54. The end of the flexible cable 48 is connected with the link 1G2 by a pin 156 which extends through the link 102 and through a loop at the end of the flexible cable 48. Removal of the pin 1S0, therefore, disconnects the flexible cable 48 from the motor mount and leaves the motor mount free to move independently of the hydrofoils.

The boat is started with the motor in the raised position to which it was brought by the lowering of the hydrofoils. As the speed of the boat increases and the hull begins to rise out of the water, the motor mount 54 is lowered progressively with respect to the boat hull by the hydraulic motor 116 so as to keep the propeller of the outboard motor properly submerged. By the time the boat is fully foilborne, the motor mount 54 is in its lowermost position.

When the boat stops, the hydraulic motor 116 is again operated to raise the motor mount so that the exhaust of the outboard motor will not be excessively submerged at the next start. If it is desired to raise the hydrofoils, each of the flexible cables 48 is again connected to its respective link 54 so that the lowering of the links by the hydraulic motor 116 will retractthe hydrofoils and the outboard motor 191 will act as a counterweight for raising the hydrofoils as previously explained.

FIGURE 5 is a diagrammatic illustration of the control means for operating the motor 116. Working fluid, such as oil, is supplied to the cylinder 120 of the motor 116 through conduits 154 and 155. The first conduit 154 supplies oil to the crank end of the cylinder and causes the cylinder to move upward and lift the pin 124 and the motor support and motor.

FIGURE 6 is a diagrammatic showing of a boat transom 11 to which 'a motor support 98' is connected by links M92 and 104'. Abutments 136' and 138 on the transom ll limit up-and-down movement of the links 102' and 104'. The motor 116 is connected with the link 102 by the pin 124. The cable 48 is connected to the link 102' by the pin which is removable, as in the construction shown in FIGURE 3.

Referring again to FIGURE 5, there is a valve 169 having an angularly-movable valve element 162 for controlling the flow of oil to and from the conduits 154 and .5 155, and for connecting these conduits 154 and 155 selectively with a pump 164 and a reservoir 66. The valve 160 is connected with the pump 164 through a conduit 168; and it is connected with the reservoir 166 through conduits 170 and 172, there being an adjustable restrictor 174 in the conduit 1797 A by-pass conduit 176 connects the valve 160 with the reservoir 166 through a pressure relief valve 178.

' FIGURE also shows a second cylinder and piston motor 180 with a piston rod 182'connected to cables 183 that pass over sheaves 184 to forward hydrofoils of the boat. These forward hydrofoils are not illustrated and it is suflicient to understand that the supply of working fluid to the motor 180 is controlled by a valve 186 similar to the valve 160 and connected to opposite ends of the cylinder of the motor 18% by conduits 188 and 189; to the pump 164 by a conduit 190; to the reservoir 166 through conduits 191 and 172; and to the valve 161 through the adjustable restrictor 174.

When the valve element 162 is in the position shown in solid lines in FIGURES 5 and 7, oil from the pump 164 flows through the conduit 154 to operate the motor to raise the pin 124 and the motor support and motor, as previously explained; and oil from the head end of the cylinder 120 flows through the conduit 155, valve 161), conduit 170, restrictor 174, and conduit 172 to the reservoir 166. The restrictor does not restrict flow toward the reservoir.

When the valve element 162 is moved into the dottedline position shown in FIGURES 5 and 7, oil is supplied from the pump 164 to the conduit 155 that leads to the head end of the cylinder 120 and this causes the motor 116 p to move downward to lower the pin 124 and the motor foils. There is a handle 1% on each of the valves 160 and 186 for changing their positions to reverse their motors. When the valves 16%) and 186 are in intermediate positions between the solid and dotted line positions, oil cannot flow either toward or from the cylinders, and the motors are, therefore, locked in whatever position they are in.

The pump 164 may be motor-driven or manually-operated. lin order to prevent the application of excessive pressure, there is a by-pass line 196 through which oil may discharge through a pressure relief valve 198 to the reservoir 165.

In the operation of the invention the boat leaves the dock with the hydrofoils 14 in their retracted positions. A motor 191 (FIGURE '6), attached to the motor support 98', is held in its raised position and the boat is operated as a displacement boat. When the boat is to be made foilborne, it is' stopped and the valve 186 is turned into its dotted-line position while the valve 166 remains in its full-line position; the motor will lower itself through gravity toward its low position at a rate controlled by the amount of fluid allowed to flow through the restrictor 174.

. The rear foils are then pushed outward by hand until the center of gravity of each of the rear foils is outside of the bearings on'which the foils pivot and the foils tendto move downward by gravity.

With the valve 160 in its solid-line position, the pump 164 is operated to supply power to the conduit 154 and to raise the pin 124 and the motor support and motor. Upward movement of the motor support causes the foils to descend into their working position, as previously explained.

The foil 32 (FIGURE 1) is locked in lowered position by connecting it with the bracket 26 by means which need not be illustrated. The cable 48 is then disconnected from the motor mount 54. The front hydrofoils are lowered into working position under control of the motor and are locked in lowered position.

The boat is then ready to become foil-borne. The throttle of the motor is opened and the thrust of the motor tends to keep its support in its high position. As the boat gains speed and the hydrofoils lift the boat, the pump 164 (FIGURE 5) is operated to supply working fluid to the motor 116 to move the pin 124 and the motor support and motor downward against the force of the propeller thrust.

The arms 1192' and 104' (FIGURE 6) reach a position where they are parallel to the direction of thrust of the motor propeller, and when these arms 102' and 104 continue to move down, the thrust of the propeller becomes effective to urge them downward and to hold them in their lowered position.

After foilborne operation, the motors and valves are operated with a generally reversed sequence to raise the hydrofoils and the motor support and motor. The relief valves are preferably adjustable; and are set to prevent overloading of the working fluid circuits in the event of sudden shock or in case the operator forgets to remove the pin 15@ which disconnects the cable 48 after the rear hydrofoils have been lowered and locked in their lowered or working position. i

The preferred embodiment of the invention has been illustrated and described but changes and modifications can be made and some features can be used in different combinations without departing from the invention as defined in the claims.

What is claimed is:

1. In a boat having a hull, hydrofoils, means connecting the hydrofoils with the hull, including bearings on which the hydrofoils swing between working and retracted positions, and in the latter position extend over part of the boat hull, rest supported from the hull and on which the hydrofoils are supported when in retracted position, each of the rests being movable orbitally about an axis extending generally fore-and-aft, and a spring operably connected with each rest and resisting orbital movement of the rest by the weight of the hydrofoil that is supported by that rest.

2. The boat described in claim 1 characterized by bearings having longitudinal axes extending generally normal to the transom and adjacent to the transom and of a length substantially as great as the thickness of the transom, shafts extending through said bearings and rotatable about said axes of the bearings, and a crank extending from each of the'shafts, one of the rests being carried by each of the cranks. v 9

3. In a hydrofoil boat having a hull with a transom, a mount at the stern of the boat for an outboard motor, means connecting the mount with the transom, and on which the mount'is movable between high and low positions to change the position of the motor about an athwart ship axis and in a vertical direction with respect to the hull, brackets connected to the hull adjacent to the stern, hydrofoils connected with the brackets, hearings on the brackets and on which the hydrofoils swing about generally fore-and-aft axes that are at a relatively fixed location with respect to the hull and between working positions and retracted positions, and common operating mechanism operably connected with the mount and hydrofoils and that moves the mountbetween its high and low positions and that moves the hydrofoils between working and retracted positions.

4. The hydrofoil boat described in claim 3, characterized by the common operating mechanism including a cylinder and piston motor with motion transmitting connections through which the motor operates both said mount and said hydrofoilsr 5. In a hydrofoil boat having a hull with a transom, hydrofoils connected with the hull by pivot connections on which the hydrofoils are movable from working positions to retracted positions in which the foils are out of the Water and located at least partially within a projection of the hull of the boat, a mount at the transom of the hull, the mount 7 having a support for an outboard motor that has an underwater exhaust, the support being connected with the transom by links, and thelinks being movable to raise and lower the motor support to-change the depth of immersion of the motor propeller in the water, mechanism connected with the motor support for raising and lowering the motor support, mechanism for moving the hydrofoils into and out of retracted positions, and common operat ing means for both of the mechanisms. 7

6. Ina hydrofoil boat having a hull and a transom, hydrofoils connected with the hull by pivot connections on which the hydrofoils are movable from working positions to retracted positions in which the foils are out of the water and located at least partially within a projection of the hull of the boat, a mount at the transom of the boat having a support for an outboard motor, the support being connected with the transom of the hull by links which are movable to raise and lower the motor support to change the depth of immersion of 'a propeller of the outboard motor, a flexible cable connecting the hydrofoils with a portion of the mount thatmoves up and down with .the motor support, said cable serving to raise the hydrofoils as the motor support moves downward and to lower the'hyd-rofoils as the motor support moves upward, and guide means through which the flexible cable passes to change its direction of travel.

7. The hydrofoil boat described in claim 6, characterized by guide means including a pulley supported by a tension elementon which the pulley swings to obtain a self aligning action with the direction of pull of the cable.

8. The hydrofoil boat described in claim 5, characterized by mechanism for raising and lowering the motor support including motor means connected with the mount for moving the motor support up and down, and releasable connectingmeans in said common operating means for operating said motor support and the hydrofoils independently of one another when said connecting means are released.

9. The hydrofoil boat described in claim 5, characterized by a mount construction in which the motor support is connected'with the transom of the hull, said constructionimcluding by a folding parallelogram linkage that causes the motor mount to move parallel to itself as it moves up and down, a center bracket of the mount in a relatively fixed position on the transom and a cylinder and piston motor connected at one end to the center bracket and at the other end to one of the links of the folding parallelogram linkage for shifting the linkage between folded and unfoldedcondition.

10. The hydrofoil boat described in claim 9, characterized: by an outboard motor on the support and'with anunderw'ater exhaust and a propeller that exerts a thrust in a certain direction in the water, the direction of thrust with respect to the horizontal being substantially constant as a result of the movement of the motor support parallel to itself, the links that connect the motor support with the transom being movable in to a position, as they approach the lower end of their strokes, in which the thrust of the propeller urges the links downward and thus exert a force to hold the motor support in its lowered position.

11. The combination with a boat having a hull, with a transom, hydrofoils connected with the hull and movable between working positions and'retracted positions in which 7 the hydrofoils are raised out of the'water, a mount at the stern of. the hull' for an outboard motor, the mount including a support to which a motor is connected,

'8 connections between the support and the transom and on which the motor support is movable to change the depth of immersion of the water on the support, and motiontransmitting connections between the support and the hydrofoils and that position the support in accordance with the positions of the hydrofoil.

12. The combination described in claim 11, characterized by operating mechanism for moving the amount to change the vertical position of the motor support, and means for locking the operating mechanism in any set position.

13. The combination described in claim 11, characterized by a motor constituting part of the operating mechanism and connected between the transom and a part of the motor mount, the motion transmitting connections between the hydrofoils and the motor mount being connected to raise the hydrofoils as the motor mount moves downward and to lower the hydrofoils as the motor mount moves upward, and a detachable connection in said motion transmitting means for disconnecting them from the motor mount whereby the motor mount can be operated independently of the hydrofoils.

14. The combination described in claim 13, characterized by the motion transmitting means including flexible cables, and including also sheaves about which the flexible cables run to change their direction of travel.

15. The combination described in claim 13, characterized by said motor being hydraulic, and a hydraulic system connected with the motor including a pump for supplying working fluid to the motor, a conduit system, and valve means in said conduit system for selectively supplying working fluid to ditferent ends of the motor to reverse its direction of movement.

16. The combination described in claim 15, characterized by a restrictor in the conduit system for regulating the flow of working fiuid through the conduit system to control the rate of movement of the motor and parts that are connected with the motor.

17. The combination described in claim 13, characterized by two hydraulic motors at spaced locations for operating hydrofoils at difierent ends of the boat, and valve means in hydraulic circuits of the motors and including two different valve elements movable into different, positions to regulate the flow of working fluid from the pump and to control any gravity actuated operation of any parts connected with the motors.

References Eited in the file of this patent UNITED STATES PATENTS (Page 88 relied on).

Yachting, vol. 103, No. 4, April 1958 (pages 69-71 relied on).

The Rudder, August 1958, vol. 74, No. 8 (Pages 6-8 and 5.8 relied on). 

1. IN A BOAT HAVING A HULL, HYDROFOILS, MEANS CONNECTING THE HYDROFOILS WITH THE HULL, INCLUDING BEARINGS ON WHICH THE HYDROFOILS SWING BETWEEN WORKING AND RETRACTED POSITIONS, AND IN THE LATTER POSITION EXTEND OVER PART OF THE BOAT HULL, REST SUPPORTED FROM THE HULL AND ON WHICH THE HYDROFOILS ARE SUPPORTED WHEN IN RETRACTED POSITION, EACH OF THE RESTS BEING MOVABLE ORBITALLY ABOUT AN AXIS EXTENDING GENERALLY FORE-AND-AFT, AND A SPRING OPERABLY CONNECTED WITH EACH REST AND RESISTING ORBITAL MOVEMENT OF THE REST BY THE WEIGHT OF THE HYDROFOIL THAT IS SUPPORTED BY THAT REST. 